我正在用python制作一个不一致的机器人，我想知道如何检查启动命令的用户是否使用client.wait_for输入了消息

import discord
from discord.ext import commands

client = commands.Bot(command_prefix='!')

@client.event
async def on_ready():
    print('Bot is ready.')

@client.command()
async def start(ctx):
    await ctx.send('Please enter a message:')
    try:
        message = await client.wait_for('message', timeout=30.0, check=lambda m: m.author == ctx.author)
        await ctx.send(f'You entered: {message.content}')
    except asyncio.TimeoutError:
        await ctx.send('You did not enter a message within the specified time.')

client.run('YOUR_BOT_TOKEN')